Definition
Slate is a fine-grained, foliated, homogeneous metamorphic rock derived from an original shale-type sedimentary rock composed of clay or volcanic ash through low-grade regional metamorphism
Coquina is a sedimentary rock that is composed either wholly or almost entirely of the transported, abraded, and mechanically-sorted fragments of the shells of molluscs, trilobites, brachiopods, or other invertebrates
Origin
England
European Foreland Basins
Discoverer
Unknown
Unknown
Etymology
From Old French esclate, from esclat (French éclat)
From Concha (Latin)+ Coquina(Spanish) +conch(English)= Couquina (mid 19th century)
Class
Metamorphic Rocks
Sedimentary Rocks
Sub-Class
Durable Rock, Medium Hardness Rock
Durable Rock, Soft Rock
Group
Not Applicable
Not Applicable
Other Categories
Fine Grained Rock, Opaque Rock
Coarse Grained Rock, Opaque Rock
Color
Black, Brown, Buff, Green, Light to Dark Grey, Purple, Red, Shades of Blue
Beige, Buff, Orange
Durability
Durable
Non-Durable
Appearance
Dull
Layered, Banded, Veined and Shiny
Interior Uses
Bathrooms, Decorative Aggregates, Entryways, Floor Tiles, Flooring, Homes, Hotels, Interior Decoration, Kitchens, Stair Treads
Decorative Aggregates, Homes, Hotels, Interior Decoration
Exterior Uses
As Building Stone, As Facing Stone, Garden Decoration, Paving Stone
Garden Decoration, Office Buildings
Other Architectural Uses
Curbing
Curbing
Construction Industry
As Dimension Stone
Building houses or walls, Construction Aggregate
Medical Industry
Not Yet Used
Not Yet Used
Antiquity Uses
Artifacts, Monuments, Sculpture, Small Figurines
Artifacts, Monuments, Sculpture, Small Figurines
Commercial Uses
Blackboards, Commemorative Tablets, Laboratory bench tops, Standard material for the bed of Billiard table, Standard material for the beds of Pool and Snooker table, Tombstones, Used in aquariums, Writing Slates
Creating Artwork
Types
Not Available
Not Available
Features
Easily splits into thin plates, Surfaces are often shiny, Very fine grained rock
Available in Lots of Colors and Patterns, Is one of the oldest rock
Archaeological Significance
Famous Monuments
Data Not Available
Data Not Available
Famous Sculptures
Data Not Available
Data Not Available
Formation
Slate is a low grade metamorphic rock that is generally formed by metamorphosis of mudstone or shale, under relatively low pressure and temperature conditions.
Coquina is a sedimentary rock which is formed when billions of small clam-like seashell, called Coquina, or cockleshell are die and hence are deposited, buried and turns into a rock when pressure is applied.
Mineral Content
Apatite, Biotite, Chlorite, Feldspar, Graphite, Hematite, Kaolinite, Magnetite, Pyrite, Tourmaline, Zircon
Apatite, Augite, Bronzite, Calcite, Chert, Chlorite, Clay Minerals, Epidote, Feldspar, Garnet, Micas, Muscovite or Illite
Compound Content
Aluminium Oxide, CaO, Iron(III) Oxide, Potassium Oxide, MgO, Sodium Oxide, Silicon Dioxide, Titanium Dioxide
CaO, Carbon Dioxide, Iron(III) Oxide, MgO
Types of Metamorphism
Burial Metamorphism, Cataclastic Metamorphism, Regional Metamorphism
Not Applicable
Types of Weathering
Biological Weathering, Chemical Weathering, Mechanical Weathering
Biological Weathering, Chemical Weathering, Mechanical Weathering
Types of Erosion
Coastal Erosion, Glacier Erosion, Water Erosion, Wind Erosion
Coastal Erosion, Sea Erosion, Water Erosion, Wind Erosion
Grain Size
Very fine-grained
Coarse Grained
Fracture
Splintery
Irregular
Streak
Light to dark brown
White
Porosity
Less Porous
Highly Porous
Luster
Dull
Dull to Vitreous to Submetallic
Compressive Strength
Not Available
Cleavage
Slaty
Not Available
Toughness
1.2
Not Available
Specific Gravity
2.65-2.8
1.10-2.24
Transparency
Opaque
Opaque
Density
2.6-2.8 g/cm3
2.8-2.9 g/cm3
Specific Heat Capacity
Not Available
Resistance
Heat Resistant, Impact Resistant, Pressure Resistant, Wear Resistant
Heat Resistant, Impact Resistant, Pressure Resistant, Wear Resistant
Deposits in Eastern Continents
Asia
China, India, Turkey
Not Yet Found
Africa
Not Yet Found
Not Yet Found
Europe
Belgium, France, Germany, Italy, Norway, Portugal, Spain, United Kingdom
United Kingdom
Others
Arctic
Not Yet Found
Deposits in Western Continents
South America
Brazil
Not Yet Found
Deposits in Oceania Continent
Australia
Not Yet Found
Not Yet Found
All about Slate and Coquina Properties
Know all about Slate and Coquina properties here. All properties of rocks are important as they define the type of rock and its application. Slate belongs to Metamorphic Rocks while Coquina belongs to Sedimentary Rocks.Texture of Slate is Foliated whereas that of Coquina is Clastic. Slate appears Dull and Coquina appears Layered, Banded, Veined and Shiny. The luster of Slate is dull while that of Coquina is dull to vitreous to submetallic. Slate is available in black, brown, buff, green, light to dark grey, purple, red, shades of blue colors whereas Coquina is available in beige, buff, orange colors. The commercial uses of Slate are blackboards, commemorative tablets, laboratory bench tops, standard material for the bed of billiard table, standard material for the beds of pool and snooker table, tombstones, used in aquariums, writing slates and that of Coquina are creating artwork.